Pictures speak for themselves really. Once I passed 5800N/10000W, autopilot started a gradual right turn for no reason, even though LNAV was set onto the next waypoint. Eventually, it stopped turning right and instead started going in circles.
Deviation starts at around 2:10 in, the heading target for the autopilot stays at 312, however it decided to turn right away from that anyway. About 7 hours in the heading target changes, and that’s when I started doing circles.
United 131 had the same fpl as me, for reference.
Device: iPad Air 2
Operating system: IOS 15.7.3